8/13/2019 Characteristics of amphibolites of Penjeween area,Kurdistan Region, northeast Iraq: Genetic implication and associ
1/24
Journal of Environment and Earth Science www.iiste.org
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)
Vol.3, No.14, 2013
22
Characteristics of the amphibolite rocks of Penjween area,
Kurdistan Region, northeast Iraq: Genetic implication and
association with Penjween Ophiolite Complexes
Ayten Hadi1*Dalya Kameran2Sabah Ismael 2
1.Department of Earth Science, College of Science University of Baghdad
2.Department of Applied Geology, College of Science University of Kirkuk
* E-mail of the corresponding author: [email protected]
Abstract
Amphibolite rocks are found in Penjween ophiolite complexes within the Iraqi Zagros Thrust Zone, northeast
Iraq. They appear in a discontinuous outcrops as pods and lenses in a sharp contact with peridotite and
serpentinite rocks. Amphibole and plagioclase are the main mineral constituents with minor amount of
clinpyroxene and quartz, Fe-Ti-oxides, titanite, apatite, zircon as accessory phases. Two mineral assemblages are
recognized in these amphibolites;(1) amphibole+ plagioclase+ clinopyroxene+ iron oxides +titanite quartz
apatite zircon;(2) amphibole+ plagioclase +iron oxide+ titanite quartz apatite zircon, with chlorite, epidote
and actinolite as secondary mineral phases. These amphibolites show different textures as granoblastic,
granonematobalstic, porphyroblastic, and poikiloblastic. The amphiboles are calcic (Ca>1 apuf) and are of two
types; Mg- hornblende and tschermakite. They are characterized by: SiO2(38.83-47.48%), Al2O3(7.97-16.02%),
TiO2 (0.28-3.04%), MgO (12.03-16.38%), Cao (11.01-12.46%), FeO (8.55-13.4%) and Mg*(0.62-0.76).
Plagioclase composition ranges between oligoclase (An23.4-Ab75.9) and albite (An1.7-Ab97.9).
Geothermobarometry based on TiO2-Al2O3 isopleths of calcic amphibole show that both Mg-hornblende and
tschermakite have P range (1.5-2.5 GPa) and T range (550-700C) for Mg-hornblende and (700-900C) for
tschermakite, which are within amphibolite facies grade. Geochemical characteristics of these amphibolites
indicate their igneous origin of tholeiitic basalt affinity with sub-alkaline basalt and andesite protoliths that are
formed by fractionation of clinopyroxene, plagioclase and Fe-Ti- oxides. Primitive mantle- normalized trace
elements diagram show similarity with subduction zone setting with striking variable enrichment of LILE,depletion of HFSE and HREE, and negative Nb-Ta anomalies. Chondrite normalized-REE diagram show LREE
enrichment (La/Sm)N= 3.295, (La/Yb)N= 3.919 indicating the existence of garnet as residual phase in the source
mantle. Tectonic discrimination diagrams based on immobile elements suggest island arc tholeiite, specifically
back-arc basin basalt setting with 5-25% partial melting. The negative Nb-Ta anomalies, high Th and Ba/Yb, and
La/Nb< 5, all confirm the back-arc basin setting or supra-subduction zone environment. This is consistent with
the proposed idea that these amphibolites are genetically related to Penjween ophiolite and represent oceanic
crustal rocks and sea-floor sediments that were detached and emplaced by mantle rocks of the ophiolite onto the
Arabian Plate margin during Late Cretaceous. The processes of detachment and emplacement cause
metamorphism of the oceanic crustal rocks reaching amphibolite facies grade.
Key words:Amphibolite, Penjween ophiolite, SSZ
1. Introduction
The Iraqi Zagros Thrust Zone (IZTZ) represents the suture zone between the Arabian and Iranian Plates. This
zone extends in a northwest-southeast direction from the Turkish-lranian border as a result of the collision
between the Arabian and Eurasian Plates which occurred during Cenozoic Time (Stckline, 1968, Alavi, 1994,
2004). It is considered as a part of Zagros Orogenic Belt which extends for about 2000 km. from southeast
Turkey through Syria and lraq to the western and southern Iran and is considered an integral part of the main
Alpine- Himalayan Orogenic Belt (Ricou,1976, Berberian and King,1981). Zagros Thrust Zone marks the
boundry between the Zagros Fold Belt in the west and the Zagros Suture Zone in the east and is deeply rooted
possibly to the Moho depth according to the geophysical and geological data (Agard et al, 2005, Azizi and
Moinerazir, 2009). Along this zone magmatic activity and dismembered ophiolites occurred represented by
Mawat group in the northeast Iraq comprising Mawat, Penjween, Bulfat and Pushtashan ophiolites with
associated sediments, (Fig.1). These ophiolites were metamorphosed in the Late Cretaceous time and emplaced
onto the Zagros Suture Zone during the Miocene time (Jassim and Goff, 2006). The study area is located withinso-called Penjween ophiolite complex which comprises both mantle ultramafic sequence and cumulate gabbro
8/13/2019 Characteristics of amphibolites of Penjeween area,Kurdistan Region, northeast Iraq: Genetic implication and associ
2/24
Journal of Environment and Earth Science www.iiste.org
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)
Vol.3, No.14, 2013
23
and volcanics of oceanic sequence (Al-Hassan and Habbard, 1985; Mohamed, 2007). The complex had suffered
deformation and metamorphism that are associated with the igneous and sedimentary rocks. Amphibolite rocks
appeared in the area as lenses and pods in contact with the overlying ultramafic rocks, mainly peridotite and
serpentinized peridotite. However, no detail studies have been reported concerning these metamorphic rocks in
the area.The aim of the present study is to discuss the origin and thermo-barometric evolution of the amphibolite
rocks utilizing mineralogy, mineral chemistry and geochemical data and to identify the protolith, tectonic setting
of the emplacement and their relation to the associated igneous rocks in the area.
Figure -1: Generalized tectonic map of the Iraqi Zagros Thrust Zone showing the study area (Jassim and Goff,
2006).
2. Regional Geology
Zagros Orogenic Belt is considered a young continental belt that trends northwest-southeast. As a response to the
collision between Eurasia and the advancing Arabian Plate during Mesozoic time, Zagros Mountain developed
(Takin, 1972; Agard et al, 2005). According to Lippard et al (1986) continental breakup and the opening of the
Neo-Tethys occurred during Traissic time while Stampfli et al (2001) suggested the Permian time for this
opening phase. Northeast-dipping subduction of the Neo-Tethys oceanic lithosphere beneath the Sanandaj-Sirjan
continental margin in Iran occurred during the Early Jurassic, (Dercourt et al, 1986) or Middle Jurassic (Agard et
al (2005). Buday and Jassim(1987) and Jassim and Goff (2006) suggested Late Jurassic time for subduction
event which is accompanied by the formation of volcanic arc close to the northern margin of the Arabian Plate.
The intra-oceanic subduction continued until the collision with the northern Arabian Plate margin in the Late
Cretaceous time accompanied by the emplacement of ophiolite onto the Arabian continental margin (Lippard et
al,1986). After Late Cretaceous, the magmatic activity continued till Eocene time on the southern margin of the
8/13/2019 Characteristics of amphibolites of Penjeween area,Kurdistan Region, northeast Iraq: Genetic implication and associ
3/24
Journal of Environment and Earth Science www.iiste.org
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)
Vol.3, No.14, 2013
24
Sanandaj-Sirjan block with the production of magmatic rocks. The continental collision caused the tectonic
emplacement of these Eocene rocks onto the ophiolite sequences (Alavi, 1994; Allahyari et al 2010).
In northeast Iraq the Zagros Orogenic Belt is divided into the following northwest-southeast trending domains:
the Sanandaj-Sirjan, the Suture Zone, the Imbricated and the Fold-thrust Zone (Buday and Jassim, 1987). The
Sanandaj-Sirjan zone represents the extreme northeastern part within the Iraqi-Iranian border but the major parts
are in northwest Iran. It is a 150-200 km. wide and composed of deformed and metamorphosed Paleozoic-
Mesozoic rocks which are intruded by Late Cretaceous to Paleocene plutons (Stockline, 1968; Alavi, 1994; Azizi
and Jahaugiri, 2008). Shalair Zone is considered as an integral part of Sanadaj-Sirjan Zone in northeast Iraq and
represents the innermost metamorphosed and volcanic units forming the structurally highest thrust sheets. The
so-called Zagros Thrust Belt separates between the Zagros Suture Zone to the east and the Imbricated Zone to
the west (Berberian and King, 1981; Jassim and Goff, 2006; Azizi and Moinevaziri, 2009). The Imbricated Zone
consists of imbricated tectonic slices involving Qulqula radiolarite, Mawat igneous complexes, Penjween
ophiolite complexes, Mesozoic and Cenozoic volcanic and sedimentary rocks as well as the thrust sheets from
Sanandaj-Sirjan Zone. This zone represents a zone of thrust faults that have transported metamorphosed and
non-metamorphosed Phanerozoic units of the Arabian continental margin as well as ophiolite complexes of the
collisional suture zone from the northeast towards the interior parts of the Arabian Craton to the southwest
(Aswad, 1999; Mohammed, 2007). Zagros Fold-Thrust Belt to the west represents the less strained part of theorogeny and consists of a pile of folded and faulted rocks of Paleozoic and Mesozoic successions which is
overlain by Cenozoic siliciclastic and carbonate rocks that overlain metamorphosed Proterozoic Pan-African
basement (Alavi, 2004; Mohammed, 2007).
Penjween area is located within so- called Penjween-Walash sub-zone within Zagros Suture Zone and it
comprises volcano- sedimentary sequences formed during Cretaceous ocean spreading of the Neo-Tethys and is
strongly affected by magmatism (Buday and Jassim, 1987). Paleocene arc volcanics and syn-tectonic basic
intrusions formed during the final closure of Neo-Tethys Ocean during Paleocene-Eocene time (Aswad, 1999).
The zone is thus represents the remnant of the Neo-Tethys which was thrusted over the Arabian Plate during
Miocene Pliocene. The Penjween-Walash sub-zone forms an almost continuous belt along the Iraqi-Iranian
border and consists of three thrust sheets: the structurally lowest Napurdan, the middle Walash and the upper
Qandil. The upper Qandil thrust sheet comprises basic igneous massifs including Penjween, Mawat, Bulfat and
Pushtashan. The study area is located within this zone.
Penjween igneous complex is situated to the southwest of Penjween town about 40 km. to the east of
Sulaimaniye city, Kurdistan region between latitudes (35 36 16.4- 35 37 15.6 N) and longitudes (45 54
40.4-45 55 54 E), (Fig.2). It has a very complicated topography consisting of rugged mountains with
elevation reaching about 1484 m. in the root peak with very steep valleys. 15-16 pods of amphibolite rocks were
observed and sampled in the area. They occur as discontinuous bodies of different sizes and shapes in contact
with peridotite and serpentinized peridotite (Fig.3). These amphibolite pods are of lensoid shape with variable
dimensions generally ranging from 2-3 m. long and 0.5-2 m. thick of dark olive green color. They have sharp
contacts with the ultramafics and some have large scale lamination due to the gradation in grain size (Fig.4) with
some cut by 2mm. chlorite veins (Fig.5) and one in contact with albitite dyke. In addition, one amphibole gabbro
dyke of 1m. thick is recognized. This dyke is vertically trending and cut by serpentinite which grades into pure
amphibolite (Fig.6).
8/13/2019 Characteristics of amphibolites of Penjeween area,Kurdistan Region, northeast Iraq: Genetic implication and associ
4/24
Journal of Environment and Earth Science www.iiste.org
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)
Vol.3, No.14, 2013
25
Figure-2: Geologic map of Penjween showing samples locations.
8/13/2019 Characteristics of amphibolites of Penjeween area,Kurdistan Region, northeast Iraq: Genetic implication and associ
5/24
Journal of Environment and Earth Science www.iiste.org
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)
Vol.3, No.14, 2013
26
Figure-3: Field distribution of the amphibolite outcrops.
Figure-4: Large scale grain size lamination within one of the amphibolite outcrop.
8/13/2019 Characteristics of amphibolites of Penjeween area,Kurdistan Region, northeast Iraq: Genetic implication and associ
6/24
Journal of Environment and Earth Science www.iiste.org
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)
Vol.3, No.14, 2013
27
Figure-5: Chlorite veins cutting one of the amphibolite outcrop.
Figure-6: Amphibole gabbro dyke.
8/13/2019 Characteristics of amphibolites of Penjeween area,Kurdistan Region, northeast Iraq: Genetic implication and associ
7/24
Journal of Environment and Earth Science www.iiste.org
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)
Vol.3, No.14, 2013
28
3. Analytical Methods
Twenty samples of amphibolites and serpentinized peridotites among them 14 samples for amphibolite rocks are
collected with one amphibole gabbro dyke sample and one albitite dyke sample. Mineral chemical analyses were
carried out using wavelength dispersive microprobe (JEOL Super probe JXA- 8800) at the Cooperation Research
Center, Kanazawa University, Japan. Raw data for each element were corrected using ZAF program. Analytical
conditions are: 15 KV for acceleration voltage, 20nA for beam current and 3 m. for beam diameter. The
counting time is 20 sec. on the peak of the characteristic X-ray for each element. Analytical errors are
8/13/2019 Characteristics of amphibolites of Penjeween area,Kurdistan Region, northeast Iraq: Genetic implication and associ
8/24
Journal of Environment and Earth Science www.iiste.org
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)
Vol.3, No.14, 2013
29
Figure-7-a-i: Photomicrographs of the amphibolite rocks:
a-Primary amphibole and plagioclase forming granonematoblastic texture.XPL. Sample PA11.
b-Secondary amphibole penetrating primary clinopyroxene.XPL. Sample PA12.
c-Zoned amphibole crystal with subgrains around it. XPL. Sample PA2.
d-Plagioclase and amphibole phenocrysts in groundmass of the same minerals with quartz. Some of the quartz
show andulose extinction. XPL. Sample PA2.
e-Granoblastic texture of clinopyroxene and plagioclase with secondary amph-boles. XPL. Sample PA1.
f-Relict of clinopyroxene surrounded by secondary amphibole.XPL. Sample PA1.
g- Poikiloblastic texture, zircon inclusions with sericite patches within large plagioclase grain. XPL. Sample
PA12.
h-Granonematobalstic texture showing distribution of the major and accessory mineral phases. XPL. Sample
PA10.
i- Porphyroblastic texture with large amphibole and plagioclase phenocrysts. Also shows the association of
titanite(sphene) with iron oxides. XPL. Sample PA14.
4-2. Amphibole- gabbro dyke
Hornblende (57.7%) and clinopyroxene are the major mafic phases, (Fig.8-a- b). The clinpyoxene is partially
altered into amphibole and appeared as relict within amphibole. Prismatic euhedral- subhedral hornblende
observed with some showing secondary twinning (Fig.8-c). Plagioclase modally form (30- 35%) mostly fresh of
andesine composition with few showing partial alteration to epidote and sericite. Fine euhedral apatite, titanite
(sphene) and iron oxides are the common accessory minerals (Fig.8-d). Ophitic, subophitic and intergranular
textures are common.
d e f
g h i
a b c
8/13/2019 Characteristics of amphibolites of Penjeween area,Kurdistan Region, northeast Iraq: Genetic implication and associ
9/24
Journal of Environment and Earth Science www.iiste.org
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)
Vol.3, No.14, 2013
30
4.3 Other related rocks
Albititedyke is observed in the study area found in contact with one of the amphibolite pods. This albitite was
studied by Mohammed et al (2007) who concluded that the preserved texture, mineralogy and their geochemical
data in Malakawa in Penjween is plagiogranite. This albitite which is found in the study area is composedentirely of albite with accessory hornblende, pyroxene, apatite and Fe-oxides and their oxidation product
(goethite) (Fig. 8-e-f).
4.4 Geothermo-barometry
As previously mentioned, amphibole and plagioclase are the major constituents of the study amphibolites
together with quartz, titanite, apatite, ilmenite and epidote as accessory minerals. The chemical analyses of
amphibole and plagioclase are listed in tables (1) and (2) respectively. According to the classification of Leak et
al (1997), the amphiboles are calcic (Ca >1 apfu), (table-1) and are clustered in the fields of Mg-hornblende and
tschermakite (Fig.9) with SiO2 range (38.83-47.48%), Al2O3 (7.97-16.02%), TiO2 (0.28-3.04%), MgO (12.03-
16.38%), CaO(11.01-12.4%), and FeO (8.55-13.4%) with high Mg (0.62-0.76). The SiO2 content is lower in
tschermakite compared to that in Mg- hornblende whereas TiO2in tschermakite is higher. Most studies of the
paragenesis of calcic amphibole in mafic metamorphic and igneous rocks show that with increase of P T-conditions or metamorphic grade, the calcic amphibole exhibits an increase in Al, Na,Ti, Mg and decrease in Si
(Deer et al, 1998) which is influenced by O2 as well. The Al2O3content in tschermakite is higher relative to
Mg-hornblende and also [Al]4(table-1) demonstrating the attendance of [Al]4to replace Si in tetrahedral site in
these amphiboles as temperature increase. [Al]6 content is considerable in both types which indicates that there
is a substantial substitution of [Al]6for Mg and Fe in M2 octahedral site. This latter substitution that occurs in
M2 site is influenced by increase in pressure (Raase,1974), hence, Al2O3 content could be a good geo-
thermobarometric indicator. The fluid composition plays a role in the equilibration of the amphibole and the
buffer phase, therefore the association of Ti-rich phases such as titanite and ilmenite with the major phases leads
to the proposition that these amphiboles are Ti-saturated and so the solubility of Ti in both tschermakite and Mg-
hornblende is buffered by the occurance of such Ti-rich minerals. TiO2 is high reaching up to 3.04% in
tschermakite and is commonly replace Mg and Fe in M2 octahedral site (Leak et al, 1997) and the amount of
substitution increase with temperature increase, therefore, TiO2 is a good temperature indicator. Thus the
estimation of P-T conditions of metamorphism can be computed by using Al2O3 and TiO2. Figure (11) is the
Al2O3- TiO2isopleths plot of the analyzed amphiboles. The Mg-hornblende plot within temperature range 550-
700C and mostly between 700-900C for tschermakite with pressure 1-2 GPa. Jasmmond and Schafer (1972)
and Takanoba (1978) concluded that both Mg-hornblende and tschermakite solubility limits are between
temperature range 450-900C under water vapor pressure 1-3 GPa which is within the range of amphibolite
facies metamorphism grade.
Table-1: Chemical analyses of amphiboles
8/13/2019 Characteristics of amphibolites of Penjeween area,Kurdistan Region, northeast Iraq: Genetic implication and associ
10/24
Journal of Environment and Earth Science www.iiste.org
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)
Vol.3, No.14, 2013
31
Table-1: Continued
Table-2: Chemical analyses of plagioclase
8/13/2019 Characteristics of amphibolites of Penjeween area,Kurdistan Region, northeast Iraq: Genetic implication and associ
11/24
Journal of Environment and Earth Science www.iiste.org
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)
Vol.3, No.14, 2013
32
Figure 9: Chemical classification of amphiboles, (after Leak et al,1997). Apuf= atom per unit formula.
Figure 10: Chemical classification of plagioclase,(after Deer et al1963). Ab=albite, An=anorthite,
Or=orthoclase.
8/13/2019 Characteristics of amphibolites of Penjeween area,Kurdistan Region, northeast Iraq: Genetic implication and associ
12/24
Journal of Environment and Earth Science www.iiste.org
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)
Vol.3, No.14, 2013
33
Figure 11: Al2O3and TiO2isopleths(in wt%) of analyzed amphiboles on P-T diagram (after Ernst and Liu,1998).
5. Whole rock geochemistry
Bulk chemical analyses were performed for fourteen representative amphibolite samples based on the selection
of the least altered (table-3). The geochemical features of these amphibolites are described by using those
elements which are virtually immobile during alteration and metamorphism. These amphibolites are
characterized by: SiO2 (42.5-58.7%), Al2O3 (12.95-16.65%), FeO (4.5-12.9%), CaO(4.97-13.4%), MgO (5.23-
14.25%), and TiO2 (0.47-1.44%), with exception of two samples (PA4 and PA14) which have very low SiO 2,
Al2O3and MgO. The amphibolites exhibit distinct more or less coherent positive and negative correlations of the
major oxides and trace elements with SiO2 and MgO (table-3, Figs. 12a-h) reflecting amphibole, plagioclase,
clinopyroxene and Fe-Ti-oxide crystallization. In general, the geochemical criteria and relationships of these
amphibolites confirm their igneous origin; the relationship between TiO2-Cr proposed by Leak (1964) shows an
igneous protolith (ortho) by the plot of all samples outside the sedimentsry protolith (para), (Fig.13-a).
Furthermore, the high Cr/Th 100; the low Th/La~0.05, and Zr/TiO2~0.013 ; the high Ni (ava.173.3 ppm) and
Cr (ava.397.5ppm),(table-3) are all characteristics of typical igneous protolith (Taylor and Mc Lennan,1985;Rollinson,1996). Accordingly, on SiO2-K2O diagram of Peccerillo and Taylor (1976), the data fall within low-K
tholeiite field (Fig.13-b) and on Zr-Y diagram of Barret and Maclean (1999) within tholeiitic basalt field with an
average Zr/Y =2.9 except three samples which fall within the transitional field (Fig.13-c). These characteristics
of the amphibolites indicate their formation through pyroxene and plagioclase fractionations with original
protolith composition that correspond to sub-alkali basalt and andesite on Nb/Y-Zr/TiO2 diagram (Fig.13-d)
proposed by Wichester and Floyd (1977).
tschermakite Mg-hornblende
8/13/2019 Characteristics of amphibolites of Penjeween area,Kurdistan Region, northeast Iraq: Genetic implication and associ
13/24
Journal of Environment and Earth Science www.iiste.org
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)
Vol.3, No.14, 2013
34
Table-3: Whole rock chemical analyses of Penjween amphibolites
8/13/2019 Characteristics of amphibolites of Penjeween area,Kurdistan Region, northeast Iraq: Genetic implication and associ
14/24
Journal of Environment and Earth Science www.iiste.org
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)
Vol.3, No.14, 2013
35
Table-3: Continued
Figure 12: Harker variation diagrams for Penjween amphibolites showing the Trends of some major oxides and
trace elements with MgO.
8/13/2019 Characteristics of amphibolites of Penjeween area,Kurdistan Region, northeast Iraq: Genetic implication and associ
15/24
Journal of Environment and Earth Science www.iiste.org
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)
Vol.3, No.14, 2013
36
Figure 13: (a): Cr versus TiO2 diagram for Penjween amphibolites. The shaded Area represents sedimentary
protolith, the outside of the shaded Area represents igneous protolith. (after Leak,1964)
(b): K2O versus SiO2 diagram showing the plots of the amphibolites within Low-K tholeiite field, (after
Peccerillo and Taylor, 1976).
(c): Zr versus Y diagram showing distribution of the amphibolites tholiietic And transitional fields, (after
Barret and Maclean,1999).
(d): Nb/Y versus Zr/TiO2 diagram showing the possible protolith for amphi-bolites of Penjween ,(after
Winchester and Floyd, 1977).
Chondrite-normalized REE patterns for Penjween amphibolites display a regular patterns (Fig.14-a)
(normalization after Sun and McDonough, 1989). Such patterns imply a homogenous parental magma variously
affected by partial melting and fractional crystallization (Pe-piper et al, 2004; El-Shazly and Hegaze, 2000). The
concentration of REE varies in the range 10 and 100 chon. with fractionated LREE relative to MREE and
HREE (La/Sm)N= 3.295, (La/Yb)N= 3.917,(table-3), with pronounced positive Ce anomaly. Since Ce is
incompatible with the major mantle mineral phases, this indicates its accommodation in the accessory minerals
such as Fe-Ti oxides and also indicates the highly oxidizing condition environment. In addition, the decrease in
abundance of TiO2with the increase of SiO2 (table-3) and its increase with the increase of MgO and FeO confirm
crystallization of titano-magnetite and high O2 in the melt as well as in the amphibole. Slight negative Eu
anomaly is observed (Eu/Eu) = 0.859 avar.), (table-3), indicating plagioclase accumulation (Wilson,1989). Juster
et al, (1989) and Patchett et al (1994) suggested that the lack of pronounced Eu anomaly may be explained due tofractionation in highly oxidation environment of Fe-Ti- rich magma with reduced KdEu
plag-liquid. Furthermore,
a
cd
b
8/13/2019 Characteristics of amphibolites of Penjeween area,Kurdistan Region, northeast Iraq: Genetic implication and associ
16/24
Journal of Environment and Earth Science www.iiste.org
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)
Vol.3, No.14, 2013
37
the crystallization of calcic amphibole and clinopyroxene could effect on the Eu fractionation in plagioclase.
More or less flat MREE is consistent with hornblende fractionation which may either be late magmatic as
tschermakite or metamorphic as Mg-hornblende (Kocak et al, 2005). In general, the REE patterns of the
amphibolites are indicative of island arc setting. The LREE/HREE ratios display a narrow variation consistent
with the generation of magma by partial melting of mantle source in which garnet is residual phase (Wilson,1989; Watson and McKenzie, 1991).
Primitive mantle- normalized trace elements diagram is relatively uniform (Fig.14-b), (normalization after Sun
and Mc Donough, 1989) with striking variable concentrations of LILEs due to their mobilities and depletion of
HFSEs and HREEs. Pronounced negative Nb and Ta anomalies which together with the positive Th anomaly
reflect subduction-related environment nature of these amphibolites, specifically, a supra-subduction zone (SSZ)
setting environment (Pearce,1982). Ba and Sr show great variability in their concentrations relative to the rest of
the LILEs which could be due to their high mobility during metamorphism. On the other hand, Zr, Y and Yb are
among the HFSE and HREE show negative anomalies in all samples reflecting their retentions in resistant
minerals such as zircon, rutile, apatite, and sphene (titanite).
Figure 14: Chondrite-normalized REE patterns (a) and Primitive mantle-normal-Ized spider diagrams (b) for
Penjween amphibolites. Normalization Values for chondrite and primitive mantle are from Sun and McDonough,(1989).
a
b
8/13/2019 Characteristics of amphibolites of Penjeween area,Kurdistan Region, northeast Iraq: Genetic implication and associ
17/24
Journal of Environment and Earth Science www.iiste.org
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)
Vol.3, No.14, 2013
38
7. Discussion
Based upon the geochemical data and observations previously described, the Penjween amphibolites have
igneous protolith of tholeiitic basalt affinity. The paleotectonic setting and source magma as well as petrogeneticprocesses have been achieved using those elements that are considered to be immobile during alteration and
metamorphism (e.g. Zr, Ti, Y and HREEs) on various discrimination diagrams. On La/Nb versus Nb/Th
diagram, (Thompson et al, 1984), these amphibolites show the characteristic arc-setting environment (Fig.15-a).
Both Th and Nb are incompatible elements that will be bound to the liquid fraction of the partially melting rocks;
(Th) comes from the slab sediments and its content increases with increasing slab melting and dehydration in
subduction zone (Pearce, 2008; Azizi et al, 2011), hence, Nb/Th ratio refers to the influence of subduction-
related components. The low Ta content in regard to Th (table-3) coupled with the negative Ta and Nb anomalies
(Fig.14-b) suggest mixing between IAT and MORB sources as in back-arc basin basalt (BABB). Y-La/Nb
relationship (Fig.15b) is a good mean to illustrate the position of these amphibolites within BABB field with
La/Nb ratio 5 characteristic of BABB (Floyd et al, 1991) except two samples which were taken from
amphibolite in contact with gabbro dyke. Thus a preliminary model for these amphibolites is proposed in which
a back arc basin was developed on the continental crust at the leading edge of the plate which was subsequentlyinvaded by tholeiitic magma due to subduction processe. The characteristics of the amphibolites can be better
explained in terms of subduction input and mantle fertility. According to Sinton and Fryer (1987), Sinton et al
(2003), and Pearce and Stern (2006), BABB setting is characterized by high subduction input (e.g. Ba,
Sr,Th..etc) than MORB setting. The variations observed from plotting amphibolite data on Ba/Yb ratio
(subduction input) versus Nb/Yb (mantle fertility) proposed by Pearce and Stern (2006) show their position
within BABB with few within MORB array field with high Ba/Yb ratio values (Fig.16). The genesis of BABB
magma could be related to supra-subduction of mantle and/or partial melting of shallow mantle by release of
lithostatic pressure (Banerjee and Gills, 2001; Pearce, 2005; Kocak et al, 2007). LREE enrichment (La/Yb)N=
3.967 is typical of metasomatized and metamorphosed mantle rocks by supra-subduction fluids enriched in
LREEs from the fluids that accompanied subduction. For the estimation of source mantle composition and
degree of partial melting, TiO2-Yb relationship is used (Fig.17 and 18). These amphibolites show low TiO2/Yb
and Nb/Yb ratios content characteristic of BABB with the majority plotting within enriched mid-ocean basalt
(EMORB) field since BABB setting is considered to be transitional between MORB and IAT settings (Sinton
and Fryer, 1987). They show fractionation with 5-25 % partial melting within transitional zone between garnet
lherzolite and spinel lherzolite but mostly closer to the former (Fig.18) which has estimated depth around 80 km
(Wilson, 1989; Watson and McKenzie, 1991).
From field observation shows that the amphibolites of Penjween are directly related to the ultramafic rocks
of Penjween ophiolite with sharp tectonic contact although they are observed in limited and discontinuous
outcrops in the area. Geochemical characteristics and relationships as well as tectonic setting are all evidences
that these amphibolites of tholeiitic nature of SSZ environment. They are similar to other metamorphic soles as
in Turkey ( Dilek et al,1999; Dilek,2003; Celik and Delayloye, 2003; Parlak et al, 2006). According to the
obtained results and evidences we propose that during Late Cretaceous time the volcanic rocks and sea-floor
sediments were detached and eventually emplaced by oceanic crust and upper mantle rocks that were then
thrusted over the northeastern margin of the Arabian Plate. Sufficient heat and pressure that accompanied the
processes of detachment and emplacement could be enough to cause metamorphism at the base of the emplaced
ultramafic rocks. Glent and Stout (1981) evaluated the possible P-T source of the metamorphic sole beneath
Semail ophiolite of Oman and put an assumption that the dominant source P-T required for metamorphism is the
residual heat and pressure from the ophiolite emplacement and that frictional heat during thrusting had a limited
and minor effect. This dynamothermal sole beneath a supra-subduction-type ophiolite of Penjween could be
explain by two stages of subduction; subduction of the southern branch of the Neo-Tethys oceanic crust beneath
Iranian Plate during Late Cretaceous time followed by inception of a second subduction within a supra-
subduction-type Penjween ophiolite. Wakebayshi and Dilek (2000) suggested that in a supra-subduction-type
ophiolite-sole couples it is unlikely that the dynamothermal sole would be linked to the subduction that produced
the overlying supra-subduction- type ophiolite and in such settings the metamorphic sole would be older than the
ophiolite. Their conclusion appeared that the sole is younger. In the present study our conclusion based on the
results of mineral chemistry and whole rock geochemical data. Precise age determination using radiometric
dating as Ar40
/Ar39
for the amphibole is needed to clarify the age relationship between metamorphic sole-ophiolite as well as with the intrusive amphibole gabbro dyke.
8/13/2019 Characteristics of amphibolites of Penjeween area,Kurdistan Region, northeast Iraq: Genetic implication and associ
18/24
Journal of Environment and Earth Science www.iiste.org
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)
Vol.3, No.14, 2013
39
The estimated temperature condition is high (550-900 C) coupled with medium to high pressure (1~2.5 GPa)
within amphibolite facies grade, and such high grade metamorphic sole is probably compatible with subduction
initiation within SSZ lithosphere protolith rather than MORB or OIB protoliths affinities which are characterized
by high temperature-low pressure metamorphic grade ( Wakabayashi et al,2010).
The occurrence of a late- stage gabbro dyke that cross-cut one of the amphibolite pods and the peridotite gives an
inference that the basaltic magma was still available after the prograde metamorphism. Sharvaise (2001)
assumed that such late-stage magmatism in a supra-subduction zone as dykes could be possibly originated from
an asthenospheric window that underlies the displaced oceanic lithosphere in the upper plate as in Tauride
ophiolite of Turkey (Dilek and Flower,2003), and Coast Range ophiolite of California (Sharvaise ,1990).
Figure 15: (a): La/Nb versus Nb/Th tectonic discrimination diagram showing the plots of the Penjween
amphibolites within arc field,(after Thompson et al ,1984).
b
a
8/13/2019 Characteristics of amphibolites of Penjeween area,Kurdistan Region, northeast Iraq: Genetic implication and associ
19/24
Journal of Environment and Earth Science www.iiste.org
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)
Vol.3, No.14, 2013
40
(b): Y versus La/Nb tectonic discrimination diagram showing the distribution of the majority of amphibolites
within back-arc basin basalt (BABB) field, (after Floyd et al,1991).
Figure 16: Nb/Yb versus Ba/Yb diagram showing the plots of the majority of amphibolites within BABB with
few within MORB array,(after Pearce and Stern, 2006).
Figure 17: Nb/Yb versus TiO2/Yb diagram (after Pearce,2008) showing the plots of the majority of the
amphibolites within EMORB.
8/13/2019 Characteristics of amphibolites of Penjeween area,Kurdistan Region, northeast Iraq: Genetic implication and associ
20/24
Journal of Environment and Earth Science www.iiste.org
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)
Vol.3, No.14, 2013
41
Figure 18: Yb versus TiO2 diagram (after Pearce and Stern. 2006). The majority of amphibolite samples are
clustered within the transitional field between garnet lherzolite and spinel lherzolite fields. PUM=primitive uppermantle, DMM= depleted MOR mantle
8. Conclusion
Amphibolite rocks in Penjween area is found to be related to ultramafic rocks; peridotite and serpentinized
peridotite of the mantle succession of Penjween ophiolite complexe. The major mineral constituents in these
amphibolites are amphibole and plagioclase with minor clinopyroxene , iron oxides and accessory quartz,
titanite,apatite, and zircon. The amphiboles are calcic of two types; Mg-hornblende and tschermakite whereas the
plagioclase ranges in composition between oligoclase and albite. P-T condition of metamorphism revealed that
that they are within amphibolite facies grade; P (1-2.5 GPa); T (550-850 C). The main textures are granoblastic,
granonematoblastic, porphyroblastic, and poikiloblastic. Geochemical characteristics and relationships deduced
their igneous origin with tholeiitic basalt affinity of sub-alkali basalt and andesite protolith. Primitive mantle-normalized trace element diagram, chond.normalized- REE patterns and tectonomagmatic discrimination
diagrams revealed their arc and back-arc basin basalt settings of SSZ-type formed by two-stage subduction of the
southern margin of the Neo-Tethys oceanic crust beneath the Iranian Plate in Late Cretaceous. Detachment and
emplacement of the ophiolite rocks provided P-T condition for the formation of these amphibolites. Hence,
based chiefly upon the intimate association of these amphibolites with the ultramafic rocks of Penjween ophiolite
and upon their geochemical characteristics, we conclude that they represent the dynamothermal metamorphic
sole of Penjween ophiolite.
Acknowledgment
The authors acknowledge the support of the Department of Earth Science, University of Baghdad for providing
opportunity for this study. Special thanks go to Dr. Yawuz Kettaneh(University of Salahadeen,Erbil) for his
valuable comments, Mr.Muhemmed Jameel (Department of Applied Geology, Kirkuk) for his help in field work.
8/13/2019 Characteristics of amphibolites of Penjeween area,Kurdistan Region, northeast Iraq: Genetic implication and associ
21/24
Journal of Environment and Earth Science www.iiste.org
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)
Vol.3, No.14, 2013
42
References
Agard,P., Omrani,J. Jolivet,L and Mouthereau,F. (2005). Convergence history across Zagros (Iran):
constraints from collisional and earlier deformation. Int. Jour. Earth Sci., 94, 401-419.
Alavi,M.(1994). Tectonics of the Zagros orogenic belt of Iran: new data and information. Tectonophysics,
229, 211-238.
Alavi, M.(2004). Regional stratigraphy of the Zagros fold-thrust belt of Iran and its profore-land evolution.
Amer. Jour. of Sci., 304, 1-20.
Al-Hassan, M.I. and Habbard, F.H.(1985). Magma segregation in the tectonic remnant of basalt of ophiolite
of Penjween, NE Iraq. Ofioliti., 10, 139-146.
Allahyari, K., Sccani, E., Pourmoafi, M. and Beccaluva, L.(2010). Petrology of mantle peridotites and
intrusive mafic rocks from the Kermanshah ophiolitic complex (Zagros belt, Iran): implication for the
geodynamic evolution of the Neo-Tethyan oceanic branch between Arabia and Iran. Ofioliti, 35, 71-90.
Aswad, K.J. (1991). Arc-continent collision in northeast Iraq as evidenced by the Mawat and Penjween
ophiolite complexes. Rafiden Jour .Sci., 10, 51-61.
Azizi, H. and Jahangiri, A. (2008). Cretaceous subduction-related volcanism in the northern Sanadaj- SirjanZone, Iran. Jour. of Geodynamics, 45, 178-190.
Azizi, H.and Moinevaziri, H. (2009). Review of the tectonic setting of Cretaceous to Quaternary volcanism
in northeast Iran.Jour.of Geodynamics, 47, 167-179.
Azizi, H., Asahara, Y., Mehrabi, B. and Lin Chung, S. (2011). Geochronological and geochemical
constraints on the petrogenesis of high-K granite from Suffi Abad area, Sanandaj-Sirjan, NW Iran . Chemie der
Erde,doi:10.1016/j.chemer.
Banerjee,N.R. and Gills,K.M. (2001). Hydrothermal alteration in a modern supra-subduction Zone, the
Tonga fore-arc.Jour. Geoph. Res., 106, 21737-24750.
Barrett, T.J. and Maclean, W.H. (1999). Volcanic sequences, lithogeochemistry, and hydrothermal alteration
in some bimodal volcanic-associated massive sulfide system. In: Volcanic- associated massive sulfide system:
Processes and examples in modern and ancient settings. C.T. and M.D. Hannington (eds.). Rev. Econ. Geol., 8,101-131.
Berberian, M., and King, G.C.P. (1981). Toward paleogeography, and tectonic evolution of Iran. Candian
Jour. of Earth Sci., 18, 210-265.
Buday,T. and Jassim,S.Z. (1987). The Regional Geology of Iraq, vol. 2: Tectonism, Magmatism and
Metamorphism. Geol. Min.Inv., Baghdad, 352 p.
Celik,O.F. and Delaloye,M.F. (2006). Characteristics of ophiloite-related metamorphic rocks in Beysehir
ophiolitic mlange (Central Taurides, Turkey) deduced from whole rock and mineral chemistry. Jour. Asian
Earth Sci., 26, 461-476.
Deer, W.A., Howie, R.A., and Zussman, J.(1997). Rock-Forming Minerals. Geol. Soc.Lond, U.K.
Longmane, 528 p.
Dercourt, J. Zonenshian, L.P., Ricou, L.E., Kazmin, V.G. and Le Pichon X. et al (1986). GeologicalEvolution of the Tethys Belt from the Atlantic to the Pamirs since the Lias Tectonophy., 123, 241-315.
Dilek, Y., (2003), Ophiolite concept and its evolution, in Dilek, Y., and Newcomb, S, (eds.), Ophiolites
Conceptand: The Evolution of Geological Thought. Geol. Soc. Amer. SpecialPaper, 373, 116.
Dilek, Y., Thy, P., Hacker, B., Grundvig, S. (1999). Structure and petrology of Tauride ophiolites and mafic
dike intrusions (Turkey): implications for the Neo-Tethyan Ocean. Geol. Soc. Amer. Bull., 111, 1192-1216.
Dilek, Y., and Flower, M.F.J., (2003). Arc-trench rollback and fore-arc accretion: 2. A model template for
ophiolites in Albania, Cyprus, and Oman, in Dilek, Y., and Robinson, P.T. (eds.). Ophiolites in Earth History:
Geol. Soc. London Spec. Publ.218, 4368.
El-Shazly, S.M. and Hegazy, H.A. (2000). Geochemistry and Petrogenesis of Late Proterozoic volcanic
sequences in Gabriel area, southeastern desert, Egypt.Jour. of Sci. ofQatar University, 20, 181-195.
Ernst, W.G. and Liu, J. (1998). Experimental equilibrium study of Al and Ti content of calcic amphibole in
MORB. A semi-quantitative thermobarometer.Amer. Mineral., 83, 952-969.
8/13/2019 Characteristics of amphibolites of Penjeween area,Kurdistan Region, northeast Iraq: Genetic implication and associ
22/24
Journal of Environment and Earth Science www.iiste.org
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)
Vol.3, No.14, 2013
43
Floyd, P.A., Kelling, G. Gokcen, S.L., Gokcen, N. (1991). Geochemistry and tectonic environment of
basaltic rocks from the Misis ophiolitic mlange, south Turkey. Chem.Geol., 89, 263-380.
Ghent, E.D. and Stout,, M.Z. (1981). Metamorphism at the base of Semail ophiolite, southeastern Oman
Mountain.Jour. Geophy. Res., 86, Spec. Issue, 2552-2571.
Jasmund, K. and Schafer, R. (1972). Experimental determination of P-T stability, its division in the mixed
crystal series tremolite- tschermakite. Contr. Mineral. Petrol., 34, 101-115.
Jassim, S.Z. and Goff, J.C. (2006). Geology of Iraq. Dolin.Prague and Moravian Museum, 341p.
Juster,T.P., Grove,T.L., Perfit,M.R. (1989). Experimental constraint on the generation of Fe- Ti basalts,
andesites, and rhodacite at Galapagos spreading center,85 W and 95W.Jour.Geophys. Res., 94, 9251-9265.
Kocak, K., Isik, F., Arslan, M., Zedef,V. (2005). Petrological and source region characteristics of ophiolitic
hornblende gabbros from the Aksaray and Kayseri regions, Central Anatolian Crystalline Complex, Turkey.
Jour. Asian Earth Sci., 25, 883-891.
Kocak, K., Kurt ,H., Zedef, V., Ferr, E.C. (2007). Characteristics of the amphibolites from Nigde
Metamorphics (Central Turkey), deduced from whole rock and mineral chemistry. Geoch. Jour., 41, 241-257.
Leak, B.E. (1964). The chemical distinction between ortho-and para-amphibolites.Jour.Petrol., 5, 238-254.
Leak, B.E., Woolley, A.R., Arps, C.E.S., Birch, W.D., Gilbert,M.C., Grice, J.D., Hawthorne,F.C., Kato,
A., Kisch, H.J., Krivovichev, V.G., Linthout, K., Laird, J. Mandarino, J.A., Maresch, W.V., Nickel, E.H., Rock,
N.M.S., Schumacher, J.C., Smith, D.C., Stephenson, N.C.N., Ungaretti, L., Whittaker, E.J.W., Youzhi, G.
(1997).Nomenclature of Amphiboles: Report of the sub-committee on amphiboles of the international
mineralogical association. Commission on new minerals and mineral names. Amer. Mineral., 82, 1019-1037.
Lippard, S.J., Shelton ,A.W., Gass, I.G..(1986). The Ophiolite of Northern Oman. Geol.Soc.London Mem.
11, 178p.
Mohammed, Y.O., Maekawa, H., Lawa,F. (2007). Mineralogy and origin of Malkawa albitite (Penjween)
from Kurdistan region, northeast Iraq. Geosphere, 3, 624-645.
Patchett, P.J., Lehnert, K., Rehkamper, M., Sieber,G. (1994).Mantle and crustal effects on the geochemistry
of Proterozoic dykes and sills in Sweden.Jour. Petrol., 35, 1095- 1125.
Pearce, J.A., (1982). Trace element characteristics of lavas from destructive plate boundaries, in Thorpe,
R.S., (ed.), Orogenic Andesites: Chichester, Wiley, 528548.
Pearce, J.A. (2005). Mantle preconditioning by melt extraction during flow: Theory and petrogenetic
implications.Jour. Petrol.,Doi: 10.1093/ Petrol./egi007.
Pearce, J.A (2008).Geochemical fingerprinting of oceanic basalts with applications to ophiolite
classification and the search for Archean oceanic crust.Lithos, 100, 14-48.
Pearce, J.A. and Stern, R.J. (2006). Origin of back-arc basin magmas: trace elements and isotope
perspective. Geophys. Monogr., 166, 63-86.
Peccerillo, A., and Taylor, S.R. (1976). Geochemistry of Eocene calc-alkaline volcanic rocks from theKastamonu area, northern Turkey. Contrib. Mineral. Petrol., 58, 81-93.
Pe-Piper, G., Tsikouras, B., Hatzi, K. (2004). Evolution of boninitic and island arc tholeiites in the Pindos
ophiolite, Greece. Geol. Mag., 141, 455-469.
Parlak, O., Yilmaz, H., and Boztug, D., (2006). Origin and tectonic significance of the metamorphic sole
and isolated dykes of the Divrigi ophiolite (Sivas, Turkey): Evidence for slab break-off prior to ophiolite
emplacement: Turkish Jour. of Earth Sci., 15, 2545.
Raase, P. (1974). Al and Ti contents of hornblende, indicators of pressure-temperature of regional
metamorphism. Contr. Mineral. Petrol., 45, 231-236.
Raase, P., Raith, M., Ackermand, D., Lal, R.K. (1986). Progressive metamorphism of mafic rocks from
greenschist to granulite facies in the Dharwar Craton of South India.Jour. Geol. 94, 261-282.
Ricou, L.E., Braud, J., Brunn, J.A. (1977). Le Zagros: Mmoire Societe Gologique de France: Hors-Srie,
8, 33-52.
8/13/2019 Characteristics of amphibolites of Penjeween area,Kurdistan Region, northeast Iraq: Genetic implication and associ
23/24
Journal of Environment and Earth Science www.iiste.org
ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online)
Vol.3, No.14, 2013
44
Rollinson, H. (1996). Using geochemical data: Evaluation, Presentation, Interpretation. Longman Ltd.
Essex, England, 352p.
Shervais, J.W., (1990). Island arc and ocean crust ophiolites; contrasts in the petrology, geochemistry and
tectonic style of ophiolite assemblages in the California Coast Ranges, in Malpas, J., Moores, E., Panayiotou,
A. and Xenophontos,C. (eds): Ophiolite oceanic crustal analogues: Proceedings of the Symposium Troodos
1987: Nicosia, Cyprus, Geological Survey Department, Ministryof Agriculture and Natural Resources, 507
520.
Shervais, J.W., (2001), Birth, death, and resurrection: The life cycle of supra-subduction zone-ophiolites:
Geochemistry, Geophysics, Geosystem (2001), doi:10.1029/2000GC000080.
Sinton, J.M., and Fryer, P.(1987). Mariana trough from 18N: Implication for the origin of back-arc basin
basalts.Jour. Geophys. Res., 92, 12782-12802.
Sinton, J.M., Ford, L.L., Mc Culloch, M.T., (2003). Magma genesis and mantle heterogeneity in Manus
back-arc basin, Papua, New Guinea.Jour. of Petrol., 44, 159-195.
Stampfli, G., Mosar, J, Faure, P., Pillevuit, A. Vannay ,J.C. (2001). Permo-Mesozoic evolution of the
western Tethys realm: The Neo-Tethys East mediterranian basin connection, in: P. Ziegler, W. Cacazza,
A.H.f. Robertson and S. Crasquin- Soleau (eds), Peri-Tethyan rift/wrench basins and passive margins. Mem.
Mus. Nat.., Peri-Tethys Mem., 5, 51-108.
Stckline, J. (1968). Structural history and tectonics of Iran: a review.Bull. Amer. Assoc. Petrol. Geol.,52,
1229-1258.
Sun, S. and McDonough, W.F. (1989). Chemical and isotopic-systematics of oceanic basalts: Implications
for mantle composition and processes, in: A.D. Saunders and M.J. Norry (eds): Magmatisms in the ocean
basins. Geol. Soc. London . Spec. Publ., 42, 313-345.
Takanobu, O. (1978). Phase relationship of Ca2Mg3Al2Si6Al2O22(OH)2- Ca2Mg3Fe2Si6Al2O22(OH)2- join at
high temperature and high pressure. The stability of tschermakite.Jour. Fac. Soc.,Hokkaido Univ., Ser. IV, 18,
339-350.
Takin, M.(1972). Iranian geology and continental drift in the Middle East.Nature, 23, 147- 150.Taylor ,S.R. and McLennan, S.M. (1985). The Continental Crust: Its Composition and Evolution.
Blackwell, London, 312p.
Thompson, R.N., Morrison, M.A., Hendry, G.L., Parry, S.J. (1984). An assessment of the relative roles of
the crust and mantle in magma genesis, an elemental approach. Philp.Trans Royal Soc. London,
310, 549-590.
Wakabayashi, J., and Dilek, Y., (2000). Spatial and temporal relations between ophiolites and their sub-
ophiolitic soles: A test of models of fore-arc ophiolite genesis, in Dilek, Y., Moores, E.M., Elthon, D., and
Nicolas, A., (eds)., Ophiolites and Oceanic Crust :New Insights from Field Studies and Ocean Drilling:
Geol.Soc.Amer.Spec.Paper, 349, 5364.
Wakabayashi ,J., Ghatak, A., Basu, A.R. (2010). Supra-subduction zone ophiolite generation, emplacement,
and initiation of subduction. A perspective from geochemistry, metamorphism, geochronology and regionalgeology. Geol. Soc. Amer., 122, 1548-1568.
Wilson, M.(1989). Igneous Petrogenesis. Unwin-Hyman, London, 456p.
Winchester, J.A. and Floyd, P.A. (1977). Geochemical discrimination of different magma series and their
differentiation products using immobile elements. Chem. Geol., 20, 325- 343.
8/13/2019 Characteristics of amphibolites of Penjeween area,Kurdistan Region, northeast Iraq: Genetic implication and associ
24/24
This academic article was published by The International Institute for Science,
Technology and Education (IISTE). The IISTE is a pioneer in the Open Access
Publishing service based in the U.S. and Europe. The aim of the institute is
Accelerating Global Knowledge Sharing.
More information about the publisher can be found in the IISTEs homepage:http://www.iiste.org
CALL FOR JOURNAL PAPERS
The IISTE is currently hosting more than 30 peer-reviewed academic journals and
collaborating with academic institutions around the world. Theres no deadline for
submission. Prospective authors of IISTE journals can find the submission
instruction on the following page: http://www.iiste.org/journals/ The IISTE
editorial team promises to the review and publish all the qualified submissions in a
fastmanner. All the journals articles are available online to the readers all over the
world without financial, legal, or technical barriers other than those inseparable from
gaining access to the internet itself. Printed version of the journals is also available
upon request of readers and authors.
MORE RESOURCES
Book publication information:http://www.iiste.org/book/
Recent conferences: http://www.iiste.org/conference/
IISTE Knowledge Sharing Partners
EBSCO, Index Copernicus, Ulrich's Periodicals Directory, JournalTOCS, PKP Open
Archives Harvester, Bielefeld Academic Search Engine, Elektronische
Zeitschriftenbibliothek EZB, Open J-Gate, OCLC WorldCat, Universe Digtial
Library , NewJour, Google Scholar
http://www.iiste.org/http://www.iiste.org/http://www.iiste.org/journals/http://www.iiste.org/journals/http://www.iiste.org/book/http://www.iiste.org/book/http://www.iiste.org/book/http://www.iiste.org/conference/http://www.iiste.org/conference/http://www.iiste.org/conference/http://www.iiste.org/book/http://www.iiste.org/journals/http://www.iiste.org/